I've seen these two food ingredients in soups, sauces, and some other things. I was wondering what they are? Are they another form of MSG? I assume they are some type of food enhancer. I'm trying not to eat much MSG at all, cause a lot of people get negative reactions to consuming it.

They are flavor enhancer like glutamate...(MSG is the sodium salt of glutamic acid, a dietary protein.)

The Japanes call this kind of flavor "umami" which is roughly, "meaty" or "savory" but I feel it as more a stimulation for the back of the tongue. It sort of causes the food to taste in the whole mouth.
I'll sometimes taste a soup I've made and find it a bit "thin tasting" and then I'll use some MSG to "enrich" the flavor. Too much, and the soup is ruined.

Like any complex proteins, people can be allergic to one or more of them and these people must be very careful reading labels, or eating in Oriental restaurants.

Coincidentally I just finished a bag of Ramen Soup for lunch and I pulled the empty bag. Sure enough: MSG, disodium inosinate and disodium guanylate.

Thanks for the reply. I guess a reaction to MSG is common, since I noticed over the years that a lot of Chinese Food places list in their menus that they don't use MSG. Instead of using a questionable food enhancer like that, why don't people use something else for flavor like herbs or spices?

MSG is not REALLY so terrible an additive if you think about it...just the sodium salt of glutamic acid, which is an amino acid ABSOLUTELY essential to life and sodium is well, SODIUM.

Believe me, if MSG was so dangerous a food additive as some people claim, the streets of Chinatown would be littered with corpses piled 10 deep. Sometimes I think it's just a whipping boy..picture someone turning his nose up at some MSG on steamed Chinese veg and getting a Big Mac instead.

Global demand of this stuff is nearly 2 million TONS with more than half consumed in China. I use it by the pinchful and have never had a problem.